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<table width="100%" summary="page for radarImage"><tr><td>radarImage</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Satellite Radar Image Data from near Munich</h2>

<h3>Description</h3>

<p>The data were supplied by A. Frery.  They are a part of a synthetic aperture
satellite radar image corresponding to a suburb of Munich.  Provided
are coordinates and values corresponding to three frequency bands for
each of 1573 pixels.
</p>


<h3>Usage</h3>

<pre>data(radarImage, package="robustbase")</pre>


<h3>Format</h3>

<p>A data frame with 1573 observations on the following 5 variables.
</p>

<dl>
<dt><code>X.coord</code></dt><dd><p>a numeric vector</p>
</dd>
<dt><code>Y.coord</code></dt><dd><p>a numeric vector</p>
</dd>
<dt><code>Band.1</code></dt><dd><p>a numeric vector</p>
</dd>
<dt><code>Band.2</code></dt><dd><p>a numeric vector</p>
</dd>
<dt><code>Band.3</code></dt><dd><p>a numeric vector</p>
</dd>
</dl>



<h3>Source</h3>

<p>The website accompanying the MMY-book:
<a href="http://www.wiley.com/legacy/wileychi/robust_statistics">http://www.wiley.com/legacy/wileychi/robust_statistics</a>
</p>


<h3>Examples</h3>

<pre>
data(radarImage)
plot(Y.coord ~ X.coord, data = radarImage)

## The 8 "clear" outliers (see also below)
ii8 &lt;- c(1548:1549, 1553:1554, 1565:1566, 1570:1571)
outF &lt;- 1+(seq_len(nrow(radarImage)) %in% ii8)
pairs(radarImage[, 3:5], main = "radarImage (n = 1573)",
      col = outF, pch=outF)

## Finding outliers -----------------------------------------

set.seed(1)
system.time(cc.ri &lt;- covMcd(radarImage))# ~ 0.1 sec
## check for covMcd() consistency:
iiO &lt;- as.integer(
 c(262, 450:451, 480:481, 509, 535, 542, 597, 643, 669, 697, 803:804, 832:834,
   862:864, 892, 989, 1123, 1145, 1223:1224, 1232:1233, 1249:1250, 1267, 1303,
   1347, 1357, 1375, 1411, 1419:1420, 1443, 1453, 1504, 1510:1512,
   1518:1521, 1525:1526, 1543:1544, 1546:1555, 1557:1558, 1561:1562, 1564:1566,
   1569:1571, 1573))
length(iiO) # 73 -- other seeds sometimes give 72, rarely 71 "outliers"
isO &lt;- cc.ri$mcd.wt == 0
stopifnot(identical(iiO, which(isO)),
          identical(ii8, which(cc.ri$mah &gt; 100)),
          length(intersect(cc.ri$best, iiO)) == 0)

cc &lt;- c(adjustcolor("black", 0.4), adjustcolor("tomato", 0.8))
pairs(radarImage, main = "radarImage (n = 1573) + Outliers", gap=0,
      col = cc[1+isO], pch = c(1,8)[1+isO], cex = 0.8)
</pre>


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